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dc.contributor.advisorGarcia-Perez, Manuel
dc.creatorStankovikj, Filip
dc.date.accessioned2018-05-08T16:51:43Z
dc.date.available2018-05-08T16:51:43Z
dc.date.issued2017
dc.identifier.urihttp://hdl.handle.net/2376/12943
dc.descriptionThesis (Ph.D.), Biological and Agricultural Engineering, Washington State Universityen_US
dc.description.abstractFast pyrolysis oils represent most viable renewable sources for production of fuels and chemicals, and they could supplement significant portion of the depleting fossil fuels in near future. Progress on their utilization is impeded by their thermal and storage instability, lack of understanding of their complex composition and behavior during upgrading, including the poorly described water soluble fraction (WS). This work offers two new methodologies for simplified, and sensible description of the pyrolysis oils in terms of functional groups and chemical macro-families, augments our understanding of the composition of the WS, and the behavior of the heavy non-volatile fraction during pyrolysis oils stabilization. The concept of analyzing the volatile and non-volatile fraction in terms of functional groups has been introduced, and the quantification power of spectroscopic techniques (FTIR, 1H-NMR, UV fluorescence) for phenols, carbonyl and carboxyl groups was shown. The FT-ICR-MS van Krevelen diagram revealed the importance of dehydration reactions in pyrolysis oils and the presence of “pyrolytic humins” was hypothesized. For the first time the WS was analyzed with plethora of analytical techniques. This lead to proposition of a new characterization scheme based on functional groups, describing 90-100 wt.% of the bio-oils. The structure of idealized “pyrolytic humin” was further described as a random combination of 3-8 units of dehydrated sugars, coniferyl-type phenols, furans, and carboxylic acids attached on a 2,5-dioxo-6-hydroxyhexanal (DHH) backbone rich in carbonyl groups. TG-FTIR studies resulted in defining rules for fitting pyrolysis oils’ DTG curves and assignment of TG residue. This second method is reliable for estimation of water content, light volatiles, WS and WIS. Finally, stabilization of two oils was analyzed through the prism of functional groups. Carbonyl and hydroxyl groups interconverted. The first attempt to follow silent 31P-NMR oxygen was presented; the O content reduced from 6 to 2%, which correlated well with the additional water formed. The water formation increased with stabilization temperature (3 to 10%), dominated by repolymerization instead deoxygenation. This last study presents a methodological framework for analysis of pyrolysis oils hydrotreatment; it simplifies modeling of these systems, vital for further understanding of bio-oil upgrading.en_US
dc.description.sponsorshipWashington State University, Biological and Agricultural Engineeringen_US
dc.language.isoEnglishen_US
dc.rightsIn copyright
dc.rightsPublicly accessible
dc.rights.urihttp://rightsstatements.org/vocab/InC/1.0/
dc.subjectChemical engineeringen_US
dc.subjectAnalytical chemistryen_US
dc.subjectEnergyen_US
dc.subjectbio-fuelsen_US
dc.subjectcatalysisen_US
dc.subjectcharacterizationen_US
dc.subjecthydrotreatmenten_US
dc.subjectpyrolysisen_US
dc.subjectupgradingen_US
dc.titleUNDERSTANDING THE BEHAVIOR OF THE OLIGOMERIC FRACTIONS DURING PYROLYSIS OILS UPGRADINGen_US
dc.typeElectronic Thesis or Dissertation


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